1. Technical Field
This invention relates to bacterial colonies, and more particularly, to a system and method of detecting and characterizing bacterial colonies.
2. Background Information
Pathogenic bacterial contamination in products not only put the public at risk, but also is costly to companies because of routine product testing, product recalls and liabilities. For example, Listeria monocytogenes is one of the major foodborne pathogens with the highest mortality rate (20-28%) among the food pathogens. Traditional methods for detection and identification of bacterial contaminants, such as Listeria monocytogenes, typically require 3-7 days and use biochemical or antibody or nucleic acid based tests.
Nucleic acid or antibody-based methods have been successful and are used for pathogen detection by some large food manufactures and regulatory agencies. However, the ability of these methods to differentiate live from dead bacteria and specificity of different strains of closely related species, such as Listeria, are of concern. The most reliable and commonly used method for bacterial detection is the classical culture method where test samples are enriched and plated on agar plates for identification of individual colonies by biochemical or serological assays. The assays for identification of the bacterial colonies require multiple steps, and/or use sophisticated and expensive molecular tools requiring a skilled technician to operate the tests.
What is needed is a more rapid, reproducible method and system for detecting and characterizing and identifying bacterial colonies.